Selvage tightener for fabric shearing machines



April 1964 1.. D. BICKFORD 3,130,472

SELVAGEI TIGHTENER FOR FABRIC SHEARING MACHINES Filed Feb. 4, 1963 2Sheets-Sheet 1 L. D. BICKFORD 3,130,472

SELVAGE TIGHTENER FOR FABRIC SHEARING MACHINES April 28, 1964 Filed Feb.4, 1963 v 2 Sheets-Sheet 2 Iwerzioa:

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United States Patent 3,130,472 SELVAGE TIGHTENER FOR FABRIC SEARINGMACHINES Lyman l). Bickford, Springfield, Vt., assignor to Riggs &Lombard Iuc., Lowell, Mass., a corporation of Massachusetts Filed Feb.4, 1963, Ser. No. 255,854 3 Claims. (Cl. 26-15) This invention relatesto a fabric shearing machine e1nploying a rotatably mounted cylindricalrevolver having spaced shearing blades extending longitudinally thereofat its periphery and a fixed ledger knife cooperating with the bladesand adapted therewith to shear loose threads from one face of the fabricas the fabric strip is moved longitudinally in open width over the knifeand blades. Accurate shearing of the threads at said face without damageto the fabric requires that the strip be maintained taut especially atthe selvage portions which frequently are slack and in a puckeringcondition. My invention herein contemplates the employment of twoarmlike elements pivotally mounted on the frame of the machinerespectively adjacent to and outwardly of the two margins of the stripforwardly of the ledger knife and each extending therefrom inwardlytoward the opposite margin over one face of the strip. The elements arepivotally movable toward and from the strip and each is disposed toengage a marginal portion thereof under predetermined pressure contactdesigned to remove any slack or puckering condition and hold the striptaut throughout its width as it passes the ledger knife and blades. Theproduction of a novel mechanism of this nature and for performing thisfunction comprises the primary object of the invention.

These and other features of the invention will be more clearlyunderstood from the following description of an embodiment thereofillustrated in the accompanying drawings in which:

FIG. 1 is a fragmentary view of the machine taken on line 11 of FIG. 2,

FIG. 2 is a fragmentary front elevation, and

FIG. 3 is a plan View taken on line 3-3 of FIG. 2.

In the drawings, indicates the two opposite side wall frame portions ofthe machine. A cylindrical revolver 12 carried on a shaft rotatablysupported at its ends 14 on the walls is disposed therebetween withinthe frame. Spaced shearing blades 16 extend longitudinally of and aremounted in the revolver at its periphery, and a ledger knife 18 carriedon a support 20 has its cutting edge 21 disposed in cooperating shearingrelation with the blades 16.

The machine is provided with means for supporting in full width andconducting longitudinally through the machine to and past the ledgerknife and blades a strip of fabric 22 to be sheared. As the fabricpasses the cutting edge 21 of the ledger knife, the blades 16 of therotating revolver shear the loose threads from the forward face of thefabric. A cloth rest roll 24 supported at its ends on crank arms 26mounted on the walls 10 is pro vided for maintaining the forward face ofthe fabric in contact with the ledger knife. While the fabric strip issupported in full width as it passes to the shearing station, theselvage portions are frequently so slack and puckered that the fabricwould be damaged at these portions if fed to the shearing blades in suchcondition. The function of the novel feature of the invention now to bedescribed is to remove this slack and hold the strip taut throughout itswidth as it passes to the ledger knife and blades.

The embodiment of the invention illustrated in the drawings comprisestwo arms or bars 28 pivoted at 30 ice respectively to the two walls 10of the frame adjacent to and outwardly of the two margins of the stripforwardly of the ledger knife 18 and shearing blades 16. Each armextends from its pivotal mounting inwardly over one face of the stripand toward the opposite margin. As illustrated in FIG. 3, the two pivotmountings 30 of the arms 28 are disposed in a plane spaced outwardly andforwardly from the forward face of the fabric strip 22. The arms dipdownwardly about their pivots to a position inclined longitudinallyrelative to the strip and rest adjacent to their free ends on the twoselvage portions of the strip. Removal of the slack from such portionsrequires a predetermined pressure contact of the arms with the selvagesand in the drawings I have illustrated springs 32 for performing thisfunction. 'Each spring is connected to the free end of its arm and to abracket 34 fixed to the frame. Springs for giving the predeterminedpressure desired can be provided or each spring can embody adjustingmeans for varying this pressure. It will furthermore be understood thatother suitable means can be provided for performing this predeterminedpressure producing function, such, for example, as pneumatic orhydraulic means. The pressure contact of the arms on the selvages takesup any slack therein and holds the strip taut as it passes to the ledgerknife and shearing blades, thereby effecting high shearing efliciencywithout damage to the fabric.

Having thus disclosed my invention what I claim as new and desire tosecure by Letters Patent is:

1. In a cloth shearing machine, a frame, a cylinder rotatably mounted atits ends in the frame and having a plurality of spaced shearing bladesextending longitudinally thereof at its periphery, a ledger knifedisposed longitudinally of the cylinder and having one longitudinalmargin in shearing relation with the blades, means for supporting infull width and conducting longitudinally through the machine to and pastthe ledger knife and blades a strip of fabric to be sheared, tworelatively long arms pivoted to the frame respectively adjacent to andoutwardly of the two margins of the strip forwardly of the ledger knifeand each extending therefrom inwardly toward the opposite margin overand relatively inclined longitudinally to one face of the strip andmovable about its pivot axis toward and from the strip, and means formaintaining the arms pivoted in predetermined pressure contact withadjacent marginal portions of the strip at said one face, therebyremoving slack from said portions and holding the strip taut as itpasses to the ledger knife and shearing blades.

2. The combination defined in claim 1 in which said two arms arepivotally mounted on the frame in a plane spaced outwardly from saidface of the fabric strip and said means for maintaining said pressurecontact engages the arms remotely from their pivot axes.

3. The combination defined in claim 2 in which each of said arms extendsfrom its pivot axis entirely across said face of the fabric strip andthe means for maintaining each arm in said pressure contact comprises aspring connected to the arm remotely from its pivot axis and to anadjacent portion of the frame.

References Cited in the file of this patent UNITED STATES PATENTS3,107,036 Richards et al. Oct. 15, 1963 FOREIGN PATENTS 791,030 FranceSept. 16, 1935 109,931 Germany Apr. 14, 1900 211,195 Germany June 25,1909 13,775 Great Britain of 1913

1. IN A CLOTH SHEARING MACHINE, A FRAME, A CYLINDER ROTATABLY MOUNTED ATITS ENDS IN THE FRAME AND HAVING A PLURALITY OF SPACED SHEARING BLADESEXTENDING LONGITUDINALLY THEREOF AT ITS PERIPHERY, A LEDGER KNIFEDISPOSED LONGITUDINALLY OF THE CYLINDER AND HAVING ONE LONGITUDINALMARGIN IN SHEARING RELATION WITH THE BLADES, MEANS FOR SUPPORTING INFULL WIDTH AND CONDUCTING LONGITUDINALLY THROUGH THE MACHINE TO AND PASTTHE LEDGER KNIFE AND BLADES A STRIP OF FABRIC TO BE SHEARED, TWORELATIVELY LONG ARMS PIVOTED TO THE FRAME RESPECTIVELY ADJACENT TO ANDOUTWARDLY OF THE TWO MARGINS OF THE STRIP FORWARDLY OF THE LEDGER KNIFEAND EACH EXTENDING THEREFROM INWARDLY TOWARD THE OPPOSITE MARGIN OVERAND RELATIVELY INCLINED LONGITUDINALLY TO ONE FACE OF THE STRIP ANDMOVABLE ABOUT ITS PIVOT AXIS TOWARD AND FROM THE STRIP, AND MEANS FORMAINTAINING THE ARMS PIVOTED IN PREDETERMINED PRESSURE CONTACT WITHADJACENT MARGINAL PORTIONS OF THE STRIP AT SAID ONE FACE, THEREBYREMOVING SLACK FROM SAID PORTIONS